@article{VMUMM_1998_1_a3,
     author = {M. V. Medvedeva},
     title = {On sigmoidal functions},
     journal = {Vestnik Moskovskogo universiteta. Matematika, mehanika},
     pages = {16--20},
     publisher = {mathdoc},
     number = {1},
     year = {1998},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/VMUMM_1998_1_a3/}
}